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The impact of coastal urbanization on the structure of phytobenthic communities in southern Brazil Full text
2012
Martins, Cintia D.L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos C. | Chow, Fungyi | Pereira, Sonia B. | Horta, Paulo A.
The impact of coastal urbanization on the structure of phytobenthic communities in southern Brazil Full text
2012
Martins, Cintia D.L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos C. | Chow, Fungyi | Pereira, Sonia B. | Horta, Paulo A.
The anthropogenic pressures on coastal areas represent important factors affecting local, regional, and even global patterns of distribution and abundance of benthic organisms. This report undertakes a comparative analysis of the community structure of rocky shore intertidal phytobenthos in both pristine like environments (PLE) and urbanized environments (UBE) in southern Brazil, characterizing variations on different spatial scales. Multivariate analysis of variance indicated that the PLE is characterized by a larger number of taxa and an increased occurrence of Rhodophyta species in relation to UBE. In contrast, UBE were dominated by opportunistic algae, such as Cladophora and Ulva spp. Significance tests further indicated higher species richness and Shannon–Wiener diversity on the PLE in relation to UBE. Here we provide data showing the magnitude of seaweed biodiversity loss and discuss direct and indirect consequences of unplanned urbanization on these communities.
Show more [+] Less [-]The impact of coastal urbanization on the structure of phytobenthic communities in southern Brazil | Marine Pollution Bulletin Full text
2012
Martins, Cintia D. L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos de Castro | Chow, Fungyi | Pereira, Sônia Maria Barreto | Horta, Paulo A. | Martins, Cintia D. L. | Arantes, Noele | Faveri, Caroline | Batista, Manuela B. | Oliveira, Eurico C. | Pagliosa, Paulo R. | Fonseca, Alessandra L. | Nunes, José Marcos de Castro | Chow, Fungyi | Pereira, Sônia Maria Barreto | Horta, Paulo A.
Texto completo: acesso restrito. p. 772–778 | The anthropogenic pressures on coastal areas represent important factors affecting local, regional, and even global patterns of distribution and abundance of benthic organisms. This report undertakes a comparative analysis of the community structure of rocky shore intertidal phytobenthos in both pristine like environments (PLE) and urbanized environments (UBE) in southern Brazil, characterizing variations on different spatial scales. Multivariate analysis of variance indicated that the PLE is characterized by a larger number of taxa and an increased occurrence of Rhodophyta species in relation to UBE. In contrast, UBE were dominated by opportunistic algae, such as Cladophora and Ulva spp. Significance tests further indicated higher species richness and Shannon–Wiener diversity on the PLE in relation to UBE. Here we provide data showing the magnitude of seaweed biodiversity loss and discuss direct and indirect consequences of unplanned urbanization on these communities.
Show more [+] Less [-]Metazooplankton communities in the Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia): Spatiotemporal variations and trophic relationships Full text
2012
Pagano, Marc | Sagarra, Pascual-Boi | Champalbert, Gisèle | Bouvy, Marc | Dupuy, Christine | Thomas, Yoann | Charpy, Loïc
Metazooplankton communities in the Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia): Spatiotemporal variations and trophic relationships Full text
2012
Pagano, Marc | Sagarra, Pascual-Boi | Champalbert, Gisèle | Bouvy, Marc | Dupuy, Christine | Thomas, Yoann | Charpy, Loïc
Metazooplankton abundance, biomass (<80μm, 200–500μm and >500μm) and community structure in the Ahe atoll were studied together with their relationships with environmental factors (temperature, salinity, wind) and trophic factors (phytoplankton, bacteria, heterotrophic nanoflagellates (HNF) and ciliates) during three periods in 2008–2009. Meroplankton, mainly bivalve and gastropod larvae, was dominant. Holoplankton was dominated by copepods, the main species being Oithona spp., Paracalanus parvus, Clausocalanus spp., Corycaeus spp., Acartia fossae and Undinula vulgaris. The results suggest a clear wind influence on the structure and horizontal distribution of the zooplankton communities. The metazooplankton appeared to be controlled mainly by food resources, suggesting a bottom-up control. The low nanophytoplankton biomass in contrast to the high abundance of picophytoplankton, HNF and nano-particle grazers (mainly Oithona spp., Paracalanus and bivalve larvae) highlighted the importance of the microbial loop in the food web.
Show more [+] Less [-]Metazooplankton communities in the Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia): Spatiotemporal variations and trophic relationships Full text
2012
Pagano, Marc | Sagarra, Pascual-boi | Champalbert, Gisele | Bouvy, Marc | Dupuy, Christine | Thomas, Yoann | Charpy, Loic
Metazooplankton abundance, biomass (<80 mu m, 200-500 mu m and >500 mu m) and community structure in the Ahe atoll were studied together with their relationships with environmental factors (temperature, salinity, wind) and trophic factors (phytoplankton, bacteria, heterotrophic nanoflagellates (HNF) and ciliates) during three periods in 2008-2009. Meroplankton, mainly bivalve and gastropod larvae, was dominant. Holoplankton was dominated by copepods, the main species being Oithona spp., Paracalanus parvus, Clausocalanus spp., Corycaeus spp., Acartia fossae and Undinula vulgaris. The results suggest a clear wind influence on the structure and horizontal distribution of the zooplankton communities. The metazooplankton appeared to be controlled mainly by food resources, suggesting a bottom-up control. The low nanophytoplankton biomass in contrast to the high abundance of picophytoplankton, HNF and nano-particle grazers (mainly Oithona spp., Paracalanus and bivalve larvae) highlighted the importance of the microbial loop in the food web. (C) 2012 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Macrobenthic community structure in the northern Saudi waters of the Gulf, 14years after the 1991 oil spill Full text
2012
Joydas, T.V. | Qurban, Mohammad A. | Al-Suwailem, Abdulaziz | Krishnakumar, P.K. | Nazeer, Zahid | Cali, N.A.
The 1991 Gulf oil spill heavily impacted the coastal areas of the Saudi waters of the Arabian Gulf and recent studies have indicated that even 15years after the incident, macrobenthos had not completely recovered in the sheltered bays in the affected region such as, Manifa Bay. This study investigates the community conditions of macrobenthos in the open waters in one of the impacted areas, Al-Khafji waters, about 14years after the spill. Diversity measures and community structure analyses indicate a healthy status of polychaete communities. The BOPA index reveals that oil sensitive amphipods were recolonized in the study area. This confirms that the benthic communities of the oil spill impacted area had taken only <14 years to recover in the open waters of the impacted areas. The study also reveals the existence of three distinct polychaete communities along the depth and sediment gradients.
Show more [+] Less [-]Aspects of the digestive gland cells of the mussel Mytilus galloprovincialis, in relation to lysosomal enzymes, lipofuscin presence and shell size: Contribution in the assessment of marine pollution biomarkers Full text
2012
Raftopoulou, E.K. | Dimitriadis, V.K.
The present study investigates the histochemical localization of N-acetyl-β-hexozaminidase (Hex), acid phosphatase (AcP) and β-glucuronidase (β-Gus) in the digestive gland of mussels Mytilus galloprovincialis, as well as the clarification of suitable enzyme for biomarkers’ application dealing with lysosomes. The results show more intense and homogenous localization of Hex, in relation to AcP and β-Gus and, thus, Hex histochemistry is supported as more suitable procedure for the evaluation of “lysosomal membrane stability” and “morphometrical alterations of lysosomes”. The affection of lipofuscin granules on lysosomal enzymes’ activity is also discussed. Additionally, the present study examines the response of small- and large-sized mussels M. galloprovincialis by assessing the “lysosomal membrane stability”, “morphometrical alterations of lysosomes”, “lysosomal response index (LRI)” and “structural epithelial changes in digestive tubules”. The results indicate appreciable alterations of the above parameters in large-sized mussels, supporting their greater influence by the environmental factors, in relation to small-sized ones.
Show more [+] Less [-]Low altitude remote-sensing method to monitor marine and beach litter of various colors using a balloon equipped with a digital camera Full text
2012
Kako, Shin’ichiro | Isobe, Atsuhiko | Magome, Shinya
This study aims to establish a low-altitude remote sensing system for surveying litter on a beach or the ocean using a remote-controlled digital camera suspended from a balloon filled with helium gas. The resultant images are processed to identify the litter using projective transformation method and color difference in the CIELUV color space. Low-altitude remote sensing experimental observations were conducted on two locations in Japan. Although the sizes of the litter and the areas covered are distorted in the original photographs taken at various angles and heights, the proposed image process system is capable of identifying object positions with a high degree of accuracy (1–3m). Furthermore, the color difference approach in the CIELUV color space used in this study is well capable of extracting pixels of litter objects of various colors allowing us to estimate the number of objects from the photographs.
Show more [+] Less [-]Role of living environments in the accumulation characteristics of heavy metals in fishes and crabs in the Yangtze River Estuary, China Full text
2012
Zhao, Shou | Feng, Chenghong | Quan, Weimin | Chen, Xiaofeng | Niu, Junfeng | Shen, Zhenyao
Correlation of heavy metals in the tissues of typical organisms (i.e., fishes and crabs) and those in their living environments (i.e., surface water, bottom water, and sediment) in Yangtze River Estuary has been qualitatively and quantitatively analyzed. Metal levels followed the trend: sediments >Eriocheir sinensis>Eriocheir leptognathus>benthic fish>pelagic fish>bottom water>surface water. Tissues in fishes and crabs of different species and sizes had diverse metal bioaccumulation characteristics, which was significantly affected by environment factors and their living habits. Metal levels in legs of crabs, and heads and skins of fishes showed significant correlations with those in their living environments. Collichthys lucidus is an effective bioindicator for assessing metal levels in water. No significant health risk was identified by the estimated daily intake and target hazard quotients analyses.
Show more [+] Less [-]Asia–Pacific mussel watch for emerging pollutants: Distribution of synthetic musks and benzotriazole UV stabilizers in Asian and US coastal waters Full text
2012
Nakata, Haruhiko | Shinohara, Ryu-Ichi | Nakazawa, Yusuke | Isobe, Tomohiko | Sudaryanto, Agus | Subramanian, Annamalai | Tanabe, Shinsuke | Zakaria, Mohamad Pauzi | Zheng, Gene J. | Lam, Paul K.S. | Kim, Eun-Young | Min, Byung-Yoon | We, Sung-Ug | Viet, Pham Hung | Dūc Sʹāṅ Tānā, | Prudente, Maricar | Frank, Donnell | Lauenstein, G. G. | Kannan, Kurunthachalam
We analyzed 68 green and blue mussels collected from Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Vietnam and the USA during 2003 and 2007, to elucidate the occurrence and widespread distributions of emerging pollutants, synthetic musks and benzotriazole UV stabilizers (BUVSs) in Asia–Pacific coastal waters. Synthetic musks and BUVSs were detected in mussels from all countries, suggesting their ubiquitous contamination and widespread distribution. High concentrations of musks and BUVSs were detected in mussels from Japan and Korea, where the levels were comparable or greater than those of PCBs, DDTs and PBDEs. Significant correlations were found between the concentrations of HHCB and AHTN, and also between the concentrations of UV-327 and UV-328, which suggest similar sources and compositions of these compounds in commercial and industrial products. To our knowledge, this is the first study of large-scale monitoring of synthetic musks and BUVSs in Asia–Pacific coastal waters.
Show more [+] Less [-]Identifying fluorescent pulp mill effluent in the Gulf of Maine and its watershed Full text
2012
Cawley, Kaelin M. | Butler, Kenna D. | Aiken, George R. | Larsen, Laurel G. | Huntington, Thomas G. | McKnight, Diane M.
Using fluorescence spectroscopy and parallel factor analysis (PARAFAC) we characterized and modeled the fluorescence properties of dissolved organic matter (DOM) in samples from the Penobscot River, Androscoggin River, Penobscot Bay, and the Gulf of Maine (GoM). We analyzed excitation-emission matrices (EEMs) using an existing PARAFAC model (Cory and McKnight, 2005) and created a system-specific model with seven components (GoM PARAFAC). The GoM PARAFAC model contained six components similar to those in other PARAFAC models and one unique component with a spectrum similar to a residual found using the Cory and McKnight (2005) model. The unique component was abundant in samples from the Androscoggin River immediately downstream of a pulp mill effluent release site. The detection of a PARAFAC component associated with an anthropogenic source of DOM, such as pulp mill effluent, demonstrates the importance for rigorously analyzing PARAFAC residuals and developing system-specific models.
Show more [+] Less [-]Assessing confinement in coastal lagoons Full text
2012
Measures of transport scale in aquatic systems can contribute to the formulation of definitions of indicators of the system’s ecological properties. This paper addresses confinement, a specific transport scale proposed by biological scientists as a parameter that can capture and synthesize the principal properties that determine the spatial structure of biological communities in transitional environments. Currently, there is no direct experimental measure of confinement. In this study, a methodology based on the accumulation rate within a lagoon of a passive tracer of marine origin is proposed, the influences of different factors in the calculation of confinement are analyzed, and general recommendations are derived. In particular, we analyze the spatial and the temporal variability of confinement and its sensitivity to the seasonal variability of climatic forcing, the inputs from rivers and the parameterization of the tidal exchanges. The Lagoon of Venice is used as a case study.
Show more [+] Less [-]Concentration of selected radionuclides in seawater from Kuwait Full text
2012
Uddin, Saif | Ghadban, Abdul Nabi Al | Aba, Abdulaziz | Behbehani, Montaha
No baseline existed for the radionuclides in Kuwait territorial water. With changing trend in the region to embrace nuclear energy, the baseline study is imperative to create a reference and to record the influence-functioning of upcoming power plants. The first one in Bushehr, Iran is ready to start and several more are likely to come-up in UAE, Saudi Arabia and Kuwait. The present baseline concentration of the four considered radionuclide’s show low concentration of tritium, polonium, strontium and cesium; their concentration is comparable to most oceanic waters.
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